Hey there!
y-12=20
Add 12 to both sides. (do the inverse of subtraction, which is addition)
y=32
Check answer.
32-12=20 <=== checks out :)
I hope this helps!
~kaikers


<h2><u>refer </u><u>to</u><u> the</u><u> attachment</u><u> for</u><u> explanation</u></h2>
<h2><u>hope</u><u> it</u><u> helps</u></h2>
Answer:
x = 20
Step-by-step explanation:
x - 8 = 12 Add 8 to both sides
x -8 + 8 = 12 + 8 Add -8 and 8; add 12 and 8
x = 20
The height of the tree is 42.
The number is x
it is negative
the square is 28 more than 3 times itself
x²=28+3x
minus (28+3x)
x²-3x-28=0
factor
(x-7)(x+4)=0
set to zero
x-7=0
x=7
this is not the answer because we were told the number was negative
x+4=0
x=-4
correct
the number is -4
test
(-4)²=28+3(-4)
16=28-12
16=16
check
the number is -4